An power converter includes an unfolder connected to a three-phase source and has an output connection with a positive terminal, a negative terminal and a neutral terminal. The unfolder creates two unipolar piece-wise sinusoidal DC voltage waveforms offset by a half of a period. A three-input converter connected to the unfolder produces a quasi-sinusoidal output voltage across output terminals. Switches of the converter selectively connect the positive, negative and neutral inputs across the output terminals. A PWM controller controls a first duty ratio and a second duty ratio for the converter based on a phase angle of the source and a modulation index generated from an error signal related to a control variable. The duty ratios are time varying with a fundamental frequency of the source. The modulation index relates to output voltage of the converter, peak voltage or current of the source and/or peak current at the output terminals.

An electrical system can include an isolated bidirectional converter (having an input couplable to a grid connection and an output couplable to a battery) and an isolated converter (having an input coupled to the input of the isolated bidirectional converter and couplable to the grid connection, with an AC output coupled to a convenience outlet). The electrical system can further include a controller that controls operation of the converters to operate in one of a plurality of modes including a charging mode in which the isolated bidirectional converter operates in a forward direction to charge the battery and the non-isolated converter powers the convenience outlet from the grid connection, and a non-charging mode in which the isolated bidirectional converter operates in a reverse direction to power the non-isolated converter from the battery and the non-isolated converter powers the convenience outlet.

Both AC and DC Power supply systems that may be connected directly to. AC mains and are integrated on silicon are described. The AC systems include both simple on/off capabilities as well as phase control capabilities. The DC power supply may be fixed, adjustable as through a potentiometer and programmable. The power supply systems use newly invented components of AC/DC converters and bidirectional MOSFET switches.

An apparatus includes a DC-to-AC converter comprising a first output terminal and a second output terminal. The apparatus also includes a DC-to-DC converter comprising a third output. The DC-to-AC converter is configured to receive a DC input voltage from a DC power source, and to produce a first alternating output voltage at the first output terminal, and a second alternating output voltage at the second output terminal. The DC-to-DC converter is configured receive a DC input voltage from the DC power source, and to step down the DC input voltage at the third output.

A partial-resonant converter is provided herein and comprises a partial resonant link formed by a magnetizing link inductor connected in parallel with a first capacitor on a primary winding side of a transformer and a second capacitor on a secondary winding side of the transformer, a pair of series connected switches coupled across the magnetizing link inductor and the first capacitor, and a plurality of forward conducting bidirectional blocking switches that connect an input source and an output load to the magnetizing link inductor during operation.

A multi-port power conversion system can have a multi-winding transformer and at least three ports. Each port can be coupled to the multi-winding transformer. Each port can have a semiconductor bridge and a coupling network. For each port, the semiconductor bridge can have two or more levels and can comprise at least two switches. The coupling network for each port can comprise at least one inductor. The semiconductor bridge can be coupled to the multi-winding transformer via the respective coupling network. The multi-port power conversion system can have a multi-active bridge (MAB) architecture that is universally applicable to AC-DC, DC-DC, DC-AC, and AC-AC conversion applications and extendable to any number of ports.

Apparatus and methods for supplying DC power to control circuitry of a matrix converter is provided. In certain embodiments, a matrix converter includes an array of switches having AC inputs for receiving a multi-phase AC input voltage and AC outputs for providing a multi-phase AC output voltage to a load, such as an electric motor. The matrix converter further includes control circuitry for opening or closing individual switches of the array, and a clamp circuit connected between the AC inputs and AC outputs of the array and operable to dissipate energy of the load in response to an overvoltage condition, such as an overvoltage condition arising during shutdown. The clamp circuit includes a switched mode power supply operable to generate a DC supply voltage for the control circuitry.

Disclosed is an AC-AC power converter with multiple AC voltage output branches. The AC-AC power converter is bridgeless and contains only one power stage. The AC-AC power converter consists of only one inductor for power conversion and provides a current source for successively feeding multiple output branches one at a time. Each output branch can be selected by the corresponding switch and its resonant circuit turns the input current source into an AC power source.

A system for controlling and regulating the AC voltage level delivered to a load regardless of the varying input AC voltage comprises a high frequency AC series voltage regulator coupled with a low frequency operating mains transformer. In one embodiment, the LF operating mains transformer operates at electrical mains frequency, which is typically 50 Hz or 60 Hz. The magnetic core of the LF operating mains transformer may be made of industry standard low frequency core material selected from a material group including silicon steel and amorphous core such as ‘Metglass’. The AC series voltage regulator is connected to the primary of the LF operating mains transformer, and the secondary of the LF operating mains transformer is connected in series between the mains input (which receives the unregulated input AC voltage to be regulated) and its output (which outputs the regulated AC voltage to the loads).

A power conversion apparatus includes: matrix converter circuitry configured to perform bidirectional power conversion between a primary side and a secondary side; and control circuitry configured to: calculate a deterioration level based on a secondary side current of the matrix converter circuitry, a carrier frequency, and a primary-secondary frequency difference between a primary side frequency and a secondary side frequency of the matrix converter circuitry; and output a deterioration notification in response to determining that the deterioration level exceeds a predetermined level.